Anything could make a good discussion as long as it is not racist, biased, rude, or spamming. Good discussions also has or will get discussions. The discussion you just started counts as a good discussion. Anyways, do not concentrate too much on trying to get many responses to your discussions. Just concentrate on making a discussion on questions you feel that needs to be answered or discussed about.

Any discussion can be a good discussion.
Just make sure it is a quality discussion, and try not to just make it a question, expand yourself in what you are trying to say.
Some people get more or less responses on there discussions, that's only because some people may find a better interest in a certain discussion than others.
So some people may enjoy the discussion, while other's might think it's annoying and useless.
All the best!